On tlie structnre of Taeiiia gigantea (Peters). 385 



call make out practically iio musculature except at its extremities. 

 The distal extreniity, passes, after folding- upon itself, into a muscular 

 walled tubule which riins to the marg'inal cirrus through a mass of 

 hyaline flbrillated tissiie wliich surrounds it closely. This tubule 

 opens throngh a sphincter into tlie elong-ated muscular cirrus which 

 is a somewhat club-shaped sac giving rise. at the margin of the 

 proglottis, to an eversible barbed tnbe which projects into the cir- 

 cular genital pouch. The cirrus itself is quite muscular being pro- 

 Aided witli longitudinal and circular muscles and is lined by a thick 

 cuticle. It is supplied externally with numeroiis radiating muscular 

 Strands, thick bundles of whicli extend back into the body of the 

 proglottis. It is loosely embedded in the surrounding tissue, and in 

 some portions of this very loose tissue one can make out large, clear 

 cells with very large nuclei whose function is not very obvious. The 

 tapering walls of the cirrus appear to pass into those of the filiform 

 penis which is almost chitinous in its character. It is covered by 

 numerous rows of minute hooklets and is apparently capable of turning 

 upon itself. In a number of sections no other opening could be found 

 in the genital pouch, but in one or two the penis seems to enter, by 

 being recurved toward the proglottis, an indefinite canal in the 

 margin of this sac, so that its extreniity comes to lie in a rounded 

 sac which is embedded in the substance of the parenchyma side by 

 side with the cirrus. This sac lias in no instance any other outlet. 

 It is smoothly rounded off, not surrounded by any particular muscu- 

 lature and is filled with spermatozoa. These, like the spermatozoa 

 which distend the cirrus sac, are apparently fresh and show no ad- 

 mixture of any anomalous cells or crystals. The significance of this 

 thin-walled sac is not very clear. No other female genital outlet 

 can be found on examination of a number of segments, so that it 

 seems possible that it should be regarded as the termination of an 

 otherwise obliterated vagina. Its inconstancy, since it is found only 

 in a few of the segments, seems to support this view. 



The female genitalia. The ovary lies toward the posterior 

 margin of the proglottis, distant from tlie genital margin by one-third 

 of the transverse diameter and toward the ventral surface. It is small 

 and rather pear-shaped, somewhat indistinctly outlined and contains 

 large ova with deeply staining protoplasm and distinct nucleus. It gives 

 off an oviduct which is at first thin-Avalled but soon becomes surrounded 

 by a thick, almost spherical sphincter-like structure comparable to 

 that described by Moniez, Pintner and others as the "sphincter 



